Hi, Eddie
Nicely done! Looks reasonably professional to me! At the very least,
you've made a good effort to quantify your results in a meaningful and
repeatable way, with decent tools. No need to tune your sense antennas, as
long as there is enough signal level and dynamic range for your FS
measurements.
Congrats on having mad some meaningful quantitative measurements! Thanks for
sharing!
73,
Charlie, K4OTV
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Eduardo
Araujo
Sent: Friday, September 20, 2013 8:32 AM
To: Topband
Subject: Re: Topband: Measuring Vertical input parameters while installing
radials
Hi friends,
I finished sending the measurements data to all that
requested it. In case somebody didn´t receive it yet, please let me know.
Even though I did not mention it before, I also have Field Strength
measurement synchronized in time with the AIM measurements.
As surely this was not a professional procedure, I will explain how I did it
and you may judge if it is useful for you or not.
- I installed 2 verticals antennas 3 mts long, at about 300-350 meters from
the tower base in two opposite directions. So measurement was done at ground
level.
- I did not tuned up the elements in any way, they were connected to the FS
instrument directly and as ground connection I used a 50 cm aluminum pipe
buried in the ground
- As a FS meter I used a DIGI - FIELD from IC- Engineering
- First 2 radials were installed more or less in the direction of the RX
verticals
- From there, they were installed consecutive in counter-clock wise. (look
from above)
- I used 20W at 1840 during daylight, and matched the antenna input for
every change in radial number. I used an MFJ-962B for this purpose.
- After all readings were done, I calibrate the readings against an HP-8640B
signal to visualize which was the change in db
Botton line - the measured change at ground level between 2 and 114 radials
was between 5.2 in one direction and 5.8 db to the other.
I understand this is not a professional procedure nor professional equipment
and it was done having fun enjoying the hobby.
I will like to hear from you your thought about if this kind of measurement
done at ground level and at that distance from the antenna base has a
correlation to actual radiated Field at the maximum vertical azimuth of the
vertical whichever it is.
And, also, How the procedure or elements I used could be improved ....still
within amateur measurement accuracy and not professional level.
'73 to all..... Eddie, LU2DKT
----------------------------------------------------------------------------
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From: Eduardo Araujo <er_araujo@yahoo.com>
To: Topband <topband@contesting.com>
Sent: Thursday, September 12, 2013 9:28 AM
Subject: Measuring Vertical input parameters while installing radials
Hi everyone, I recently complete the installation of +100 1/4 radials for
the 1/4 vertical.
I measured input vertical parameters using AIM4170 from 1600 to 2000Kc
I assumed it is not something new for many of you, but I wonder if the
information I collected may be of interest for some of the group members.
I have available for sharing BMP or JPG images of each scan which were run
at 2, 4, 8, 16, 32, 60 and +110 radials. Also, I have the .scn files for
each scan which could be viewed using AIM4170 SW even though you don´t have
the unit.
The good thing looking at the files using the sw is that you can move the
cursor and have all the values at all fcies from 1600-2000 Kc
In case someone is interested, let me know and I will see the way to share
it.
´73 to everyone.... Eddie, LU2DKT
PS: By the way, what a nice toy the AIM !!!, Even though I bought it more
than one year ago, this is the first time I use it
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Topband Reflector
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Topband Reflector
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